Try this: press the Win + i, privacy keys, check the "allow applications to access the camera" box. Check also if you have activated the top option that says "Allow access to the camera on this device"In the same section of settings, check In the list that leaves the applications that can access the camera, logically it must have activated the one that refers to the camera.
After this, try again to open the camera.

I just did the test on my MSI laptop where I have always blocked access to the camera and I can not make the camera work either. I get the same error message. So it makes me think that it can be when updating Windows with the configuration of the camera already blocked, or that it gives problems the last versions of Windows with the camera if it has blocked any permission. Many users are located on the internet with this type of error in the camera application with Windows 10.